st: What are the practical uses of the -offset- option?

Is there a catalogue of the various practical uses of the -offset()- option
(available in -logit-, -probit-, -ologit-, -oprobit-, . . .)? I couldn't
find any general description for its intended use(s) in the Stata User's
Guide, Programming manual (didn't really expect to see anything there on it,
anyway) or in the Reference manuals for the commands that have it as an
option. Its description under the Options sections of the various commands
that offer it is pretty brief and doesn't lend any insight as to what it's
for.
I knew of its use in profiling the log-likelihood to obtain likelihood-ratio
confidence intervals--there's one user-written command (-logprof-) by Mark
Pearce that automates the process for one estimation command
(-logit-/-logistic-), and I've used Bill Gould's -bisect- for the same
purpose for -probit- and -ologit-. But I'm not aware of anything
comprehensive written on -offset()-'s applications beyond that. Today I
stumbled across another application remeniscient to likelihood profiling,
except that it doesn't search for log-likelihood values and doesn't
calculate a deviance: hypothesis testing of a regression coefficient at an
alternative-hypothesis value different from its maximum likelihood estimate.
-findit offset- doesn't turn up anything on-target. Is there a source for
the beginner that I could refer to?
Joseph Coveney
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